[192777] in North American Network Operators' Group
Re: nested prefixes in Internet
daemon@ATHENA.MIT.EDU (Niels Bakker)
Mon Nov 21 07:01:38 2016
X-Original-To: nanog@nanog.org
Date: Mon, 21 Nov 2016 13:01:33 +0100
From: Niels Bakker <niels=nanog@bakker.net>
To: nanog@nanog.org
Mail-Followup-To: nanog@nanog.org
In-Reply-To: <20161119131005.GA29511@admin.sibptus.transneft.ru>
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* vas@mpeks.tomsk.su (Victor Sudakov) [Sun 20 Nov 2016, 03:07 CET]:
>I have reports that in case (2), some operators (e.g. Rostelecom)
>don't accept the /24 or even /23 prefix on the grounds that it is
>part of a larger /19 route already present in the routing table.
>
>Could they have a reason not to accept these more specific prefixes
>other than a whim?
If you announce a prefix you must deliver traffic sent to addresses
covered by it. You don't go announcing 0.0.0.0/0 to your peers either.
If a customer takes a /24 and announces it elsewhere, a transit
provider runs the risk of accepting inbound traffic without having
the possibility to bill their customer for it if it accepts more
specifics from e.g. a peer.
-- Niels.
